Grid-Tied vs Off-Grid vs Hybrid Solar in California

A grid-tied system is solar panels and an inverter, wired to your main panel and the utility — no battery. When the sun is up, your home runs on solar and any extra flows to the grid; when it is not, you pull power from the grid like normal. Because there is no battery to buy, it has the lowest upfront cost and the simplest design, which is why it is by far the most common setup for California homes.

One thing surprises people: a grid-tied system does not keep your lights on in a blackout. When the utility goes down, the inverter is required to stop energizing the grid within the time required by the applicable interconnection standard, so it cannot back-feed a line that a repair crew believes is dead. That safety behavior is called anti-islanding (required under UL 1741 / IEEE 1547). No battery, no backup — the panels sit idle until the grid returns.

What about the power you export? You earn export credits, but how much they are worth — and how they offset later bills — depends on your utility and tariff. Legacy NEM, the current Net Billing Tariff, and LADWP’s municipal programs all credit differently, so “grid-tied” economics are not one number. More on that below.

A hybrid system is a grid-tied system plus a battery — still connected to the utility, but now able to store solar instead of exporting all of it. Hybrid has become common among new Net Billing Tariff customers — CPUC reported nearly 70% of NBT customers paired solar with batteries by the end of 2024. Two reasons drive it.

Backup. When the grid fails, a hybrid system can island safely and keep chosen circuits running on the battery — fridge, lights, internet, a few outlets, or more if the battery and design allow. How much of the house it covers is its own decision, which we break down in whole-home vs critical-loads backup.

Self-consumption. Under the Net Billing Tariff (NEM 3.0) on SCE, PG&E and SDG&E, midday exports earn a low, time-varying credit — so it often pays to store that solar and use it in the expensive evening instead of selling it cheap. That is the core reason batteries moved to the center of solar design. Whether the battery is worth it for your bill is a separate question, covered in do you need a battery under NEM 3.0?

An off-grid system has no utility connection at all. Your panels charge a large battery bank, the battery runs the house day and night, and a backup generator covers long cloudy stretches. There is no electric bill because there is no electric account — but you are now your own utility, responsible for sizing every kilowatt-hour for the worst week of the year.

That independence is expensive. Off-grid residential systems vary dramatically with load, autonomy target, generator strategy and battery capacity, and can be several times the cost of a comparable grid-connected system, because the battery bank alone is the single largest cost and you still need a generator on top (these are illustrative ranges, not a quote). The design has to be conservative: undersize the battery and you sit in the dark; oversize it and you overpay.

In most of Los Angeles and the San Fernando Valley, going off-grid on purpose makes little sense — the grid is already at the property, utility disconnection is not always permitted in developed areas, and staying connected is cheaper and more reliable. Off-grid is genuinely the best (or only) option mainly for remote parcels where running a utility line would cost a fortune. As with any battery or backup design, the electrical details depend on your equipment, your AHJ and the applicable NEC edition, and final approval depends on code review.

Often, yes — and plenty of homeowners do exactly that: install grid-tied solar now for the lowest price, then retrofit a battery later to turn it into a hybrid system. There are two broad ways to do it. A hybrid inverter handles both solar and battery from the start, so it is the cleanest path if you already know you want storage. If you have an existing solar-only system, a battery is usually added by AC-coupling — the battery has its own inverter and ties in alongside your solar.

Whether your specific setup can accept a battery, and how it is wired for backup, depends on your inverter, your main panel, your AHJ and the applicable NEC edition and utility rules — final approval depends on code review. It is worth telling your installer up front if you might add storage later, so today’s design leaves room for it rather than forcing a costlier retrofit.

It comes down to cost and reliability. The grid provides reliable balancing power when your panels aren’t producing — though under the Net Billing Tariff imports and exports are billed at different rates, so it is not a free one-for-one battery. It takes your excess solar during the day and returns power at night, without you buying and maintaining a battery bank sized for the worst week of winter. Replicating that with off-grid hardware is what pushes those systems to double the price. So the real choice for almost every California home is not grid-tied vs off-grid — it is grid-tied vs hybrid: solar alone for the lowest price, or solar plus a battery for outage backup and better self-consumption. Off-grid stays a niche for places the grid doesn’t reach.